Inclinometers are used in rod pumping systems to measure the angle of a walking beam. This measurement is helpful for determining the operating status of a rod pumping system. For example, an inclinometer installed on a beam of a polished rod pumping system may be used to determine the running distance of the polished rod during pumping operation. Based on the polished rod running distance, information on the pump running status can be obtained.
Existing inclinometers are typically powered by an external power supply, which is often an independent power source needing regular replacement and maintenance. U.S. Pat. No. 7,219,723 to Barnes shows an example of an external power supply. Because the power supply is external to the inclinometer, resulting wires are easily damaged due to the environment (e.g., water and heat). Water can also leak into the inclinometer at the places where the external wires are connected to the inclinometer. Furthermore, installation of the inclinometer is difficult due to the separate external power supply and other external components such as antennas. Attaching such an inclinometer to the walking beam can be awkward, but placement should be precise in order to obtain accurate measurements.